1. Field of the Invention
The invention relates to a disassembleable and reassembleable sealing device for pipelines, especially for sealing the reactor coolant nozzles of a reactor pressure vessel when connected reactor loop components such as main coolant pumps or stem generators are drained for performing inspection or maintenance work thereon, with a cylindrical sealing insert which is fitted with at least one sealing ring at the outer periphery thereof, the sealing ring being disposed at the peripheral and circular shoulder surface of a ring seat being fitted to the inner periphery of the pipeline or nozzles to be sealed and being insertible into the pipeline or nozzles, wherein the diameter of the sealing ring can be increased in such a manner that it is pressed tight against the inner periphery of the pipelines or nozzles and against its ring seat surfaces.
2. Description of the Prior Art
Such a sealing device is known from European Pat. No. 0 014 878. The sealing insert disclosed therein is assembled at the site of the seal, i.e., within the piping or nozzle section to be sealed, from individual washer sections, and its convex side as well as its periphery are covered with a tight ribber skin which changes at the outer circumference of the sealing insert into an inflatable sealing ring. The sealing, insert is locked in its position by adjustable radially movable latches which engage corresponding recesses at the inner periphery of the nozzle. Furthermore, more than one washer-like sealing insert with a sealing skin and one or more inflatable sealing rings, may be provided in the device under discussion. This conventional sealing insert requires a relatively large expenditure for positioning, assembly and disassembly; this is because these operations can generally only be performed in situ by a service crew. The prior art sealing insert is not suitable, or is only suitable to a limited degree, for remotely controlled insertion and disassembly. Unless it is desired to drain the reactor pressure vessel, the disassembly and reassembly must be performed with diving equipment.